Oxime ester compound and photopolymerization initiator containing the same

ABSTRACT

An oxime ester compound of formula (I) useful as a photopolymerization initiator. A photopolymerization initiator having the oxime ester compound as an active ingredient is activated through efficient absorption of light of long wavelength, e.g., 405 nm or 365 nm, to exhibit high sensitivity. 
     
       
         
         
             
             
         
       
     
     In formula (I), R 1  and R 2  are each R 11 , OR 11 , COR 11 , SR 11 , CONR 12 R 13 , or CN; R 11 , R 12 , and R 13  are each hydrogen, a C1-C20 alkyl group, C6-C30 aryl group, a C7-C30 arylalkyl group, or a C2-C20 heterocyclic group; R 3  and R 4  are each R 11 , OR 11 , SR 11 , COR 11 , CONR 12 R 13 , NR 12 COR 11 , OCOR 11 , COOR 11 , SCOR 11 , OCSR 11 , COSR 11 , CSOR 11 , CN, halogen, or a hydroxyl group; a and b is each 0 to 4; X is oxygen, sulfur, selenium, CR 31 R 32 , CO, NR 33 , or PR 34 ; and R 31 , R 32 , R 33 , and R 34  each have the same meaning as R 1 .

TECHNICAL FIELD

This invention relates to a novel oxime ester compound useful as aphotopolymerization initiator in a photosensitive composition, aphotopolymerization initiator containing the oxime ester compound as anactive ingredient, and a photosensitive composition containing apolymerizable compound having an ethylenically unsaturated bond and thephotopolymerization initiator.

BACKGROUND ART

A photosensitive composition contains a polymerizable compound having anethylenically unsaturated bond and a photopolymerization initiator. Aphotosensitive composition polymerizes to cure on being irradiated withlight of 405 nm or 365 nm and is used in photo-curing inks,photosensitive printing plate precursors, and various photoresists.

Patent documents 1 to 8 listed below propose using an O-acyl oximecompound having a carbazolyl structure as a photopolymerizationinitiator of a photosensitive composition. However, the known O-acyloxime compounds are not sufficiently satisfactory particularly insensitivity.

Patent document 1: JP 2001-302871APatent document 2: JP 2004-534797APatent document 3: JP 2005-25169APatent document 4: JP 2005-128483APatent document 5: JP 2005-242279APatent document 6: JP 2005-242280APatent document 7: JP 2006-16545APatent document 8: JP 3754065B

DISCLOSURE OF THE INVENTION Problem to be Solved by the Invention

The problem to be solved is that there has been no photopolymerizationinitiator having satisfactory sensitivity.

Accordingly, an object of the invention is to provide a highly sensitivephotopolymerization initiator that is activated through efficientabsorption of light of long wavelengths, e.g., 405 nm or 365 nm.

Means for Solving the Problem

The above object is accomplished by the provision of an oxime estercompound represented by general formula (I) below and aphotopolymerization initiator containing the oxime ester compound as anactive ingredient.

wherein R¹ and R² each independently represent R¹¹, OR¹¹, COR₁₁, SR¹¹,CONR¹²R¹³, or CN; R¹¹, R¹², and R¹³ each represent a hydrogen atom, analkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 30carbon atoms, an arylalkyl group having 7 to 30 carbon atoms, or aheterocyclic group having 2 to 20 carbon atoms, the alkyl group, thearyl group, the arylalkyl group, and the heterocyclic group optionallysubstituted with OR²¹, COR²¹, SR²¹, NR²²R²³, CONR²²R²³, —NR²²—OR²³,—NCOR²²—OCOR²³, —C(═N—OR²¹)—R²², —C(═N—OCOR²¹)—R²², CN, a halogen atom,—CR²¹═CR²²R²³, —CO—CR²¹═CR²²R²³, a carboxyl group, or an epoxy group;R²¹, R²², and R²³ each independently represent a hydrogen atom, an alkylgroup having 1 to 20 carbon atoms, an aryl group having 6 to 30 carbonatoms, an arylalkyl group having 7 to 30 carbon atoms, or a heterocyclicgroup having 2 to 20 carbon atoms; the methylene units of the alkylenemoiety of the substituents represented by R¹¹, R¹², R¹³, R²¹, R²², andR²³ may be interrupted by an unsaturated linkage, an ether linkage, athioether linkage, an ester linkage, a thioester linkage, an amidolinkage, or a urethane linkage at 1 to 5 sites thereof; the alkyl moietyof the substituents represented by R¹¹, R¹², R¹³, R²¹, R²², and R²³ maybe branched or cyclic; an alkyl terminal of the substituents representedby R¹¹, R¹², R¹³, R²¹, R²², and R²³ may have an unsaturated bond; R¹²and R¹³, and R²² and R²³ may be connected to each other to form a ring;R³ and R⁴ each independently represent R¹¹, OR¹¹, SR¹¹, COR¹¹,CONR¹²R¹³, NR¹²COR¹¹, OCOR¹¹, COOR¹¹, SCOR¹¹, OCSR¹¹, COSR¹¹, CSOR¹¹,CN, a halogen atom, or a hydroxyl group; a and b each independentlyrepresent an integer of 0 to 4; X represents an oxygen atom, a sulfuratom, a selenium atom, CR³¹R³², CO, NR³³, or PR³⁴; R³¹, R³², R³³, andR³⁴ each independently represent R¹¹, OR¹¹, COR¹¹, SR¹¹, CONR¹²R¹³, orCN; when X is CR³¹R³², R³ and R⁴ may be connected to each other to forma ring, or R³ may be connected to one of the carbon atoms of the benzenering neighboring via —X— to form a cyclic structure; when X is an oxygenatom, a sulfur atom, a selenium atom, or PR³⁴, R³ may be connected toone of the carbon atoms of the benzene ring neighboring via —X— to forma ring, or R³ and R⁴ may be connected to each other to form a ring; andeach of R³¹, R³², R³³, and R³⁴ may independently be connected to eitherone of the neighboring benzene rings to form a ring.

The invention also provides a photosensitive composition containing thephotopolymerization initiator and a polymerizable compound having anethylenically unsaturated bond.

The invention also provides an alkali-developable photosensitive resincomposition containing the photopolymerization initiator and analkali-developable compound having an ethylenically unsaturated bond.

The invention also provides a colored alkali-developable photosensitiveresin composition comprising the alkali-developable photosensitive resincomposition and a colorant.

BEST MODE FOR CARRYING OUT THE INVENTION

The oxime ester compound of the invention and a photopolymerizationinitiator containing the compound as an active ingredient will bedescribed in detail.

In general formula (I), examples of the alkyl group as represented byR¹¹, R¹², R¹³, R²¹, R²², R²³, R³¹, R³², R³³, and R³⁴ include methyl,ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, t-butyl, amyl,isoamyl, t-amyl, hexyl, heptyl, octyl, isooctyl, 2-ethylhexyl, t-octyl,nonyl, isononyl, decyl, isodecyl, undecyl, vinyl, allyl, butenyl,ethynyl, propynyl, methoxyethyl, ethoxyethyl, propoxyethyl,methoxyethoxyethyl, ethoxyethoxyethyl, propoxyethoxyethyl,methoxypropyl, and 2-(benzoxazol-2′-yl) ethenyl. Preferred of them arethose having 1 to 8 carbon atoms.

Examples of the aryl group as represented by R¹¹, R¹², R¹³, R²¹, R²²,R²³, R³¹, R³², R³³, and R³⁴ include phenyl, tolyl, xylyl, ethylphenyl,chlorophenyl, naphthyl, anthryl, and phenanthryl, with those having 6 to12 carbon atoms being preferred.

Preferred examples of the arylalkyl group as represented by R¹¹, R¹²,R¹³, R²¹, R²², R²³, R³¹, R³², R³³, and R³⁴ include those having 7 to 13carbon atoms, such as benzyl, chlorobenzyl, α-methylbenzyl,α,α-dimethylbenzyl, phenylethyl, and phenylethenyl.

The heterocyclic group as represented by R¹¹, R¹², R¹³, R²¹, R²², R²³,R³¹, R³², R³³, and R³⁴ is preferably a 5- to 7-membered heterocyclicgroup, including pyridyl, pyrimidyl, furyl, thienyl, tetrahydrofuranyl,and dioxolanyl.

The ring formed by connecting R¹² and R¹³, the ring formed by connectingR²² and R²³, the ring formed by connecting R³ and R⁴, the cyclicstructure formed by connecting R³ to one of the carbon atoms of thebenzene ring neighboring via X, and the ring formed by connecting R³¹,R³², or R³³ and a neighboring benzene ring are preferably 5- to7-membered rings, such as cyclopentane, cyclohexane, cyclopentene,benzene, piperidine, morpholine, lactone, and lactam rings.

Examples of the halogen atom as a substituent of R¹¹, R¹², R¹³, R²¹,R²², R²³, R³¹, R³², R³³, and R³⁴ include fluorine, chlorine, bromine,and iodine. Examples of the heterocyclic group as a substituent of R¹¹,R¹², R¹³, R²¹, R²², R²³, R³¹, R³², R³³, and R³⁴ include 5- to 7-memberedheterocyclic rings, such as pyridyl, pyrimidyl, furyl, benzoxazol-2-yl,tetrahydropyranyl, pyrrolidyl, imidazolidyl, pyrazolidyl, thiazolidyl,isothiazolidyl, oxazolidyl, isooxazolidyl, piperidyl, piperazyl, andmorpholinyl.

Examples of the halogen atoms as represented by R³ and R⁴ includefluorine, chlorine, bromine, and iodine.

The methylene units of the alkylene moiety of the above describedsubstituents represented by R¹¹, R¹², R¹³, R²¹, R²² or R²³ may beinterrupted by an unsaturated linkage, an ether linkage, a thioetherlinkage, an ester linkage, a thioester linkage, an amido linkage, or aurethane linkage at 1 to 5 sites. The interrupting linking groups may bethe same or different. Two or more interrupting linking groups may becontinued to each other, if possible. The alkyl moiety of the abovedescribed substituents may be branched or cyclic, and the alkyl terminalof the substituents may have an unsaturated bond.

Preferred of the oxime ester compounds of general formula (I) accordingto the invention are those in which X is a sulfur atom for their highsolubility. Also preferred are those in which each of R¹ and R² is astraight chain, branched, or cyclic alkyl group with 1 to 20 carbonatoms optionally substituted with one or more of a halogen atom, OR²¹,and COR²¹; an aryl group having 6 to 30 carbon atoms optionallysubstituted with one or more of a halogen atom, OR²¹, and COR²¹; or anarylalkyl group having 7 to 30 carbon atoms optionally substituted withone or more of a halogen atom, OR²¹, and COR²¹; for their highsolubility.

More preferred are those in which X is a sulfur atom and those in whicheach of R¹ and R² is a straight chain, branched, or cyclic, optionallyhalogen-substituted alkyl group having 1 to 20 carbon atoms, anoptionally halogen-substituted aryl group having 6 to 30 carbon atoms,or an optionally halogen-substituted arylalkyl group having 7 to 30carbon atoms; for ease of synthesis and high sensitivity. Particularlypreferred are those in which R¹ is methyl or undecyl, and R² is methylor phenyl.

Examples of the preferred oxime ester compounds of general formula (I)include, but are not limited to, compound Nos. 1 through 25 below.

The process of synthesizing the oxime ester compound of general formula(I) according to the invention is not particularly limited. For example,the compound in which X is a sulfur atom is prepared in accordance withthe reaction scheme shown below.

That is, p-chloronitrobenzene 1 and thiophenol 2 are caused to react inthe presence of sodium hydroxide to obtain a sulfide compound 3. Thesulfide compound 3 is allowed to react with an acid chloride 4 in thepresence of aluminum chloride to obtain an acylated compound 5, which isthen caused to react with hydroxylamine hydrochloride to obtain an oximecompound 6. The oxime compound 6 is then caused to react with an acidanhydride 7 or an acid chloride 7′ to yield the oxime ester compound ofgeneral formula (I) wherein X is sulfur. Oxime ester compounds in whichX is oxygen, selenium, carbon, N—R⁵, or P—R¹² are prepared in accordancewith the above-described process.

The oxime ester compound of the invention is useful as an initiator forphotopolymerization of a polymerizable compound having an ethylenicallyunsaturated bond (hereinafter referred to as “ethylenically unsaturatedpolymerizable compound”).

The photosensitive composition according to the invention will then bedescribed. The photosensitive composition of the invention contains thephotopolymerization initiator having the oxime ester compound accordingto the invention as an active ingredient, an ethylenically unsaturatedpolymerizable compound, and, if desired, an inorganic filler and/or acolorant, and other optional components such as a solvent.

Any ethylenically unsaturated polymerizable compound that has been usedin a photosensitive composition can be used in the invention. Examplesinclude unsaturated aliphatic hydrocarbons, such as ethylene, propylene,butylene, isobutylene, vinyl chloride, vinylidene chloride, vinylidenefluoride, and tetrafluoroethylene; (meth)acrylic acid, α-chloroacrylicacid; itaconic acid, maleic acid, citraconic acid, fumaric acid, hymicacid, crotonic acid, isocrotonic acid, vinylacetic acid, allylaceticacid, cinnamic acid, sorbic acid, mesaconic acid, trimellitic acid,pyromellitic acid, 2,2′,3,3′-benzophenonetetracarboxylic acid,3,3,4,4′-benzophenonetetracarboxylic acid,mono[2-(meth)acryloyloxyethyl] succinate, mono[2-(meth)acryloyloxyethyl]phthalate, a mono(methacrylate) of a polymer having a carboxyl group anda hydroxyl group at both terminals, such as ω-carboxypolycaprolactonemono(meth)acrylate, hydroxyethyl (meth)acrylate.malate, hydroxypropyl(meth)acrylate.malate, dicyclopentadiene malate, and unsaturatedpolybasic acids such as a polyfunctional (meth)acrylate having onecarboxyl group and two or more (meth)acryloyl groups; 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl (meth)acrylate, glycidyl (meth)acrylate,compound Nos. 26 to 29 shown below, methyl (meth)acrylate, butyl(meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate,cyclohexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl(meth)acrylate, isononyl (meth)acrylate, stearyl (meth)acrylate, lauryl(meth)acrylate, methoxyethyl (meth)acrylate, dimethylaminomethyl(meth)acrylate, dimethylaminoethyl (meth)acrylate, aminopropyl(meth)acrylate, dimethylaminopropyl (meth)acrylate, ethoxyethyl(meth)acrylate, poly(ethoxy)ethyl (meth)acrylate, butoxyethoxyethyl(meth)acrylate, ethylhexyl (meth)acrylate, phenoxyethyl (meth)acrylate,tetrahydrofuryl (meth)acrylate, vinyl (meth)acrylate, allyl(meth)acrylate, benzyl (meth)acrylate; esters between an unsaturatedmonobasic acid and a polyhydric alcohol or polyhydric phenol, such asethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate,triethylene glycol di(meth)acrylate, polyethylene glycoldi(meth)acrylate, propylene glycol di(meth)acrylate, 1,4-butanedioldi(meth)acrylate, 1,6-hexanediol di(meth)acrylate, trimethylolethanetri(meth)acrylate, trimethylolpropane tri(meth)acrylate,dipentaerythritol penta(meth)acrylate, dipentaerythritolhexa(meth)acrylate, pentaerythritol penta(meth)acrylate, pentaerythritoltetra(meth)acrylate, pentaerythritol tri(meth)acrylate,tricyclodecanedimethylol di(meth)acrylate, tri[(meth)acryloylethyl]isocyanurate, and polyester (meth)acrylate oligomers; metal salts ofunsaturated polybasic acids, such as zinc (meth)acrylate and magnesium(meth)acrylate; unsaturated polybasic acid anhydrides, such as maleicanhydride, itaconic anhydride, citraconic anhydride,methyltetrahydrophthalic anhydride, tetrahydrophthalic anhydride,trialkyltetrahydrophthalic anhydrides,5-(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylicacid anhydride, trialkyltetrahydrophthalic anhydride-maleic anhydrideadducts, dodecenylsuccinic anhydride, and methylhymic anhydride; amidesformed between an unsaturated monobasic acid and a polyfunctional amine,such as (meth)acrylamide, methylenebis(meth)acrylamide,diethylenetriaminetris(meth) acrylamide, xylylenebis(meth)acrylamide,α-chloroacrylamide, and N-2-hydroxyethyl (meth)acrylamide; unsaturatedaldehydes, such as acrolein; unsaturated nitriles, such as(meth)acrylonitrile, α-chloroacrylonitrile, vinylidene cyanide, andallyl cyanide; unsaturated aromatic compounds, such as styrene,4-methylstyrene, 4-ethylstyrene, 4-methoxystyrene, 4-hydroxystyrene,4-chlorostyrene, divinylbenzene, vinyltoluene, vinylbenzoic acid,vinylphenol, vinylsulfonic acid, 4-vinylbenzenesulfonic acid,vinylbenzyl methyl ether, and vinylbenzyl glycidyl ether; unsaturatedketones, such as methyl vinyl ketone; unsaturated amine compounds, suchas vinylamine, allylamine, N-vinylpyrrolidone, and vinylpiperidine;vinyl alcohols, such as allyl alcohol and crotyl alcohol; vinyl ethers,such as vinyl methyl ether, vinyl ethyl ether, n-butyl vinyl ether,isobutyl vinyl ether, and allyl glycidyl ether; unsaturated imides, suchas maleimide, N-phenylmaleimide, and N-cyclohexylmaleimide; indenes,such as indene and 1-methylindene; aliphatic conjugated dienes, such as1,3-butadiene, isoprene, and chloroprene; macromonomers having amono(meth)acryloyl group at the terminal of the polymeric molecularchain thereof, such as polystyrene, polymethyl (meth)acrylate,poly-n-butyl (meth)acrylate, and polysiloxanes; vinyl chloride,vinylidene chloride, divinyl succinate, diallyl phthalate, triallylphosphate, triallyl isocyanurate, vinyl thioether, vinylimidazole,vinyloxazoline, vinylcarbazole, vinylpyrrolidone, vinylpyridine,vinylurethane compounds formed between a hydroxyl-containing vinylmonomer and a polyisocyanate compound, and vinylepoxy compounds formedbetween a hydroxyl-containing vinyl monomer and a polyepoxy compound. Ofthese ethylenically unsaturated polymerizable compounds, a(mono)methacrylate of a polymer having a carboxyl group and a hydroxylgroup at both terminals, a polyfunctional (meth)acrylate having onecarboxyl group and two or more (meth)acryloyl groups, and an esterbetween an unsaturated monobasic acid and a polyhydric alcohol orpolyhydric phenol are suited to be polymerized by using thephotopolymerization initiator containing the oxime ester compound of theinvention as an active ingredient. The polymerizable compounds may beused either individually or as a mixture of two or more thereof. The twoor more polymerizable compounds to be used in combination may be in theform of a copolymer previously prepared therefrom.

When the ethylenically unsaturated polymerizable compound is anethylenically unsaturated, alkali-developable compound, thephotosensitive composition of the invention serves as analkali-developable photosensitive resin composition. Examples of theethylenically unsaturated, alkali-developable compound include acrylicester copolymers, phenol and/or cresol novolak epoxy resins,polyphenylmethane epoxy resins having two or more epoxy groups, andresins obtained by causing an epoxy compound, such as a compoundrepresented by general formula (II) below, and an unsaturated monobasicacid to react with each other and causing the resulting reaction productto react with a polybasic acid anhydride. Preferred of them are resinsobtained by causing an epoxy compound, such as a compound represented bygeneral formula (II) below, and an unsaturated monobasic acid to reactwith each other and causing the resulting product to react with apolybasic acid anhydride. The ethylenically unsaturated,alkali-developable compound preferably contains 0.2 to 1.0 equivalentsof an unsaturated group.

wherein X¹ represents a single bond, a methylene group, an optionallyhalogen-substituted alkylidene group having 1 to 4 carbon atoms, analicyclic hydrocarbon group having 3 to 20 carbon atoms, O, S, SO₂, SS,SO, CO, OCO, or a substituent represented by formula A or B below; R⁴¹,R⁴², R⁴³, and R⁴⁴ each represent a hydrogen atom, an optionallyhalogen-substituted alkyl group having 1 to 5 carbon atoms, anoptionally halogen-substituted alkoxy group having 1 to 8 carbon atoms,an optionally halogen-substituted alkenyl group having 2 to 5 carbonatoms, or a halogen atom; and m represents an integer of 0 to 10.

wherein Y¹ represents a hydrogen atom, or a phenyl group or a cycloalkylgroup having 3 to 10 carbon atoms optionally substituted with an alkylgroup having 1 to 10 carbon atoms or an alkoxy group having 1 to 10carbon atoms; Z¹ represents an optionally halogen-substituted alkylgroup having 1 to 10 carbon atoms, an optionally halogen-substitutedalkoxy group having 1 to 10 carbon atoms, an optionallyhalogen-substituted alkenyl group having 2 to 10 carbon atoms, or ahalogen atom; and d represents an integer of 0 to 5.

Examples of the unsaturated monobasic acid which is caused to react onthe epoxy compound include acrylic acid, methacrylic acid, crotonicacid, cinnamic acid, sorbic acid, hydroxyethyl methacrylates.malate,hydroxyethyl acrylate.malate, hydroxypropyl methacrylate.malate,hydroxypropyl acrylate.malate, and dicyclopentadiene malate.

Examples of the polybasic acid anhydride that is caused to react afterthe reaction of the unsaturated monobasic acid includebiphenyltetracarboxylic acid dianhydride, tetrahydrophthalic anhydride,succinic anhydride, biphthalic anhydride, maleic anhydride, trimelliticanhydride, pyromellitic anhydride, 2,2′,3,3′-benzophenonetetracarboxylicacid anhydride, ethylene glycol bisanhydrotrimellitate, glyceroltrisanhydrotrimellitate, hexahydrophthalic anhydride,methyltetrahydrophthalic anhydride, nadic anhydride, methylnadicanhydride, trialkyltetrahydrophthalic anhydrides, hexahydrophthalicanhydride,5-(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylicacid anhydride, trialkyltetrahydrophthalic anhydride-maleic anhydrideadducts, dodecenylsuccinic anhydride, and methylhymic anhydride.

The epoxy compound and the unsaturated monobasic acid are preferablyused, on the formation of an epoxy adduct, in a molar ratio of 0.1 to1.0 carboxyl group of the unsaturated monobasic acid added per epoxygroup of the epoxy compound. The polybasic acid anhydride is preferablyused in such a molar ratio as to provide 0.1 to 1.0 acid anhydridestructure per hydroxyl group of the resulting epoxy adduct.

The reactions of the epoxy compound, unsaturated monobasic acid, andpolybasic acid anhydride are carried out in a usual manner.

In order to improve developability of the alkali-developablephotosensitive resin composition, either colored or not colored, theacid value of the ethylenically unsaturated alkali-developable compoundmay be adjusted by using a mono- or polyfunctional epoxy compound incombination with the ethylenically unsaturated, alkali-developablecompound. It is preferred that the solid content of the ethylenicallyunsaturated, alkali-developable compound to have an acid value of 5 to120 mg-KOH/g. The amount of the mono- or polyfunctional epoxy compoundto be used is preferably determined so as to satisfy the above recitedrange of acid value.

Examples of the monofunctional epoxy compound include glycidylmethacrylate, methyl glycidyl ether, ethyl glycidyl ether, propylglycidyl ether, isopropyl glycidyl ether, butyl glycidyl ether, isobutylglycidyl ether, t-butyl glycidyl ether, pentyl glycidyl ether, hexylglycidyl ether, heptyl glycidyl ether, octyl glycidyl ether, nonylglycidyl ether, decyl glycidyl ether, undecyl glycidyl ether, dodecylglycidyl ether, tridecyl glycidyl ether, tetradecyl glycidyl ether,pentadecyl glycidyl ether, hexadecyl glycidyl ether, 2-ethylhexylglycidyl ether, allyl glycidyl ether, propargyl glycidyl ether,p-methoxyethyl glycidyl ether, phenyl glycidyl ether, p-methoxyglycidylether, p-butylphenyl glycidyl ether, cresyl glycidyl ether,2-methylcresyl glycidyl ether, 4-nonylphenyl glycidyl ether, benzylglycidyl ether, p-cumylphenyl glycidyl ether, trimethyl glycidyl ether,2,3-epoxypropyl methacrylate, epoxidized soybean oil, epoxidized linseedoil, glycidyl butyrate, vinylcyclohexene monoxide,1,2-epoxy-4-vinylcyclohexane, styrene oxide, pinene oxide, methylstyreneoxide, cyclohexene oxide, propylene oxide, and compound Nos. 30 and 31below.

The polyfunctional epoxy compound is preferably at least one compoundselected from the group consisting of bisphenol epoxy compounds andglycidyl ethers. Using at least one of them is effective in providing a(colored) alkali developable photosensitive resin composition havingfurther improved characteristics. Examples of the bisphenol epoxycompounds include the epoxy compounds represented by general formula(II) and others, including hydrogenated bisphenol epoxy compounds.

Examples of the glycidyl ethers include ethylene glycol diglycidylether, propylene glycol diglycidyl ether, 1,4-butanediol diglycidylether, 1,6-hexanediol diglycidyl ether, 1,8-octanediol diglycidyl ether,1,10-decanediol diglycidyl ether, 2,2-dimethyl-1,3-propanedioldiglycidyl ether, diethylene glycol diglycidyl ether, triethylene glycoldiglycidyl ether, tetraethylene glycol diglycidyl ether, hexaethyleneglycol diglycidyl ether, 1,4-cyclohexanedimethanol diglycidyl ether,1,1,1-tri(glycidyloxymethyl)propane, 1,1,1-tri(glycidyloxymethyl)ethane,1,1,1-tri(glycidyloxymethyl)methane, and1,1,1,1-tetra(glycidyloxymethyl)methane.

Other useful polyfunctional epoxy compounds include novolak epoxycompounds, such as phenol novolak epoxy compounds, biphenyl novolakepoxy compounds, cresol novolak epoxy compounds, bisphenol A novolakepoxy compounds, and dicyclopentadiene novolak epoxy compounds;alicyclic epoxy compounds, such as 3,4-epoxy-6-methylcyclohexylmethyl3,4-epoxy-6-methylcyclohexanecarboxylate, 3,4-epoxycyclohexylmethyl3,4-epoxycyclohexanecarboxylate, and 1-epoxyethyl-3,4-epoxycyclohexane;glycidyl esters, such as diglycidyl phthalate, diglycidyltetrahydrophthalate, and glycidyl dimerate; glycidylamines, such astetraglycidyl diaminodiphenylmethane, triglycidyl p-aminophenol, andN,N-diglycidylaniline; heterocyclic epoxy compounds, such as1,3-diglycidyl-5,5-dimethylhydantoin and triglycidyl isocyanurate;dioxide compounds, such as dicyclopentadiene dioxide; naphthalene epoxycompounds, triphenylmethane epoxy compounds, and dicyclopentadiene epoxycompounds.

The amount of the photopolymerization initiator to be used in thephotosensitive composition of the invention is preferably, but notlimited to, 1 to 70 parts, more preferably 1 to 50 parts, even morepreferably 5 to 30 parts, by mass per 100 parts by mass of theethylenically unsaturated polymerizable compound.

Especially in the case when the photosensitive composition iscontemplated to be a (colored) alkali developable photosensitive resincomposition, the content of the ethylenically unsaturated, alkalidevelopable compound in the composition is preferably 1 to 20%, morepreferably 3 to 12%, by mass.

The photosensitive composition of the invention may optionally contain asolvent. Usually, solvents capable of dissolving or dispersing the abovedescribed components (such as the oxime ester compound of the inventionand the ethylenically unsaturated polymerizable compound etc.) are usedwhere necessary. Such solvents include ketones, e.g., methyl ethylketone, methyl amyl ketone, diethyl ketone, acetone, methyl isopropylketone, methyl isobutyl ketone, and cyclohexanone; ethers, such as ethylether, dioxane, tetrahydrofuran, 1,2-dimethoxyethane,1,2-diethoxyethane, and dipropylene glycol dimethyl ether; esters, suchas methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate,and n-butyl acetate; cellosolve solvents, such as ethylene glycolmonomethyl ether, ethylene glycol monoethyl ether, and propylene glycolmonoethyl ether acetate; alcohols, such as methanol, ethanol, isopropylalcohol, n-propanol, isobutanol, n-butanol, and amyl alcohol; etheresters, such as ethylene glycol monomethyl acetate, ethylene glycolmonoethyl acetate, and propylene glycol methyl acetate; BTX solvents(benzene, toluene, xylene, etc.); aliphatic hydrocarbons, such ashexane, heptane, octane, and cyclohexane; terpene hydrocarbon oils, suchas turpentine oil, D-limonene, and pinene; paraffinic solvents, such asmineral spirit, Swasol #310 (available from Cosmo Matsuyama Oil Co.,ltd.), and Solvesso #100 (available from Exxon Chemical); halogenatedaliphatic hydrocarbons, such as carbon tetrachloride, chloroform,trichloroethylene, methylene chloride, and 1,2-dichloroethane;halogenated aromatic hydrocarbons, such as chlorobenzene; carbitolsolvents, aniline, triethylamine, pyridine, acetic acid, acetonitrile,carbon disulfide, N,N-dimethylformamide, N-methylpyrrolidone, dimethylsulfoxide, and water. These solvents may be used either individually oras a mixture of two or more thereof.

Preferred of them are ketones and cellosolve solvents, particularlypropylene glycol 1-monomethyl ether 2-acetate, cyclohexanone, and so onin view of providing good compatibility between a resist and aphotopolymerization initiator in a photosensitive composition.

The photosensitive composition may further contain an inorganiccompound. Examples of the inorganic compound include metal oxides, suchas nickel oxide, iron oxide, iridium oxide, titanium oxide, zinc oxide,magnesium oxide, calcium oxide, potassium oxide, silica, and alumina;layered clay minerals, Milori blue, calcium carbonate, magnesiumcarbonate, cobalt compounds, manganese compounds, glass powder, mica,talc, kaolin, ferrocyanides, various metal sulfates, sulfides,selenides, aluminum silicate, calcium silicate, aluminum hydroxide,platinum, gold, silver, and copper. Preferred of them are titaniumoxide, silica, layered clay minerals, and silver. The inorganic compoundcontent in the photosensitive composition is preferably 0.1 to 50 parts,more preferably 0.5 to 20 parts, by mass per 100 parts by mass of theethylenically unsaturated polymerizable compound. The inorganiccompounds may be used either individually or in combination of two ormore thereof.

The inorganic compounds are used to serve as, for example, a filler, anantireflection agent, an electrically conductive agent, a stabilizer, aflame retardant, a mechanical strength improving agent, a specificwavelength absorbing agent, an ink repellent agent, and the like.

The photosensitive composition of the invention, especially the alkalidevelopable photosensitive resin composition may further contain acolorant to be formulated into a colored photosensitive composition.Pigments, dyes, and naturally occurring dyes are used as a colorant. Thecolorants may be used either individually or as a mixture of two or morethereof.

The pigments may be either organic or inorganic, including nitrosocompounds, nitro compounds, azo compounds, diazo compounds, xanthenecompounds, quinoline compounds, anthraquinone compounds, coumarincompounds, phthalocyanine compounds, isoindolinone compounds,isoindoline compounds, quinacridone compounds, anthanthrone compounds,perynone compounds, perylene compounds, diketopyrrolopyrrole compounds,thioindigo compounds, dioxazine compounds, triphenylmethane compounds,quinophthalone compounds, and naphthalenetetracarboxylic acids; metalcomplex compounds, such as azo dyes, and cyanine dyes; lake pigments;carbon black species, such as furnace black, channel black, thermalblack, acetylene black, Ketjen black, and lamp black; the carbon blacksrecited which are surface treated with an acid or an alkali; graphite,graphitized carbon black, activated carbon, carbon fiber, carbonnanotube, carbon microcoil, carbon nanohorn, carbon aerogel, fullerene;aniline black, pigment black 7, titanium black; hydrophobic resins,chromium oxide green, Milori blue, cobalt green, cobalt blue, manganesecompounds, ferrocyanides, phosphate ultramarine blue, Prussian blue,ultramarine, cerulean blue, viridian, emerald green, lead sulfate, leadyellow, zinc yellow, Bengal red (red iron (III) oxide), cadmium red,synthetic iron black, and amber. The pigments may be used eitherindividually or as a mixture thereof.

Commercially available pigments may be used, including pigment red 1, 2,3, 9, 10, 14, 17, 22, 23, 31, 38, 41, 48, 49, 88, 90, 97, 112, 119, 122,123, 144, 149, 166, 168, 169, 170, 171, 177, 179, 180, 184, 185, 192,200, 202, 209, 215, 216, 217, 220, 223, 224, 226, 227, 228, 240, 254;pigment orange 13, 31, 34, 36, 38, 43, 46, 48, 49, 51, 52, 55, 59, 60,61, 62, 64, 65, 71; pigment yellow 1, 3, 12, 13, 14, 16, 17, 20, 24, 55,60, 73, 81, 83, 86, 93, 95, 97, 98, 100, 109, 110, 113, 114, 117, 120,125, 126, 127, 129, 137, 138, 139, 147, 148, 150, 151, 152, 153, 154,166, 168, 175, 180, 185; pigment green 7, 10, 36; pigment blue 15, 15:1,15:2, 15:3, 15:4, 15:5, 15:6, 22, 24, 56, 60, 61, 62, 64; pigment violet1, 19, 23, 27, 29, 30, 32, 37, 40, 50.

Examples of the dyes include azo dyes, anthraquinone dyes, indigoiddyes, triarylmethane dyes, xanthene dyes, alizarine dyes, acridine dyes,stilbene dyes, thiazole dyes, naphthol dyes, quinoline dyes, nitro dyes,indamine dyes, oxazine dyes, phthalocyanine dyes, and cyanine dyes. Themay be used as a mixture thereof.

The amount of the colorant to be added to the photosensitive compositionis preferably 50 to 350 parts, more preferably 100 to 250 parts, by massper 100 parts by mass of the ethylenically unsaturated polymerizablecompound.

The photosensitive composition may further contain other organic polymerin addition to the ethylenically unsaturated polymerizable compound toprovide a cured product with improved characteristics. Examples of theorganic polymer include polystyrene, polymethyl methacrylate, methylmethacrylate-ethyl acrylate copolymers, poly(meth)acrylic acid,styrene-(meth)acrylic acid copolymers, (meth)acrylic acid-methylmethacrylate copolymers, ethylene-vinyl chloride copolymers,ethylene-vinyl copolymers, polyvinyl chloride resins, ABS resins, nylon6, nylon 66, nylon 12, urethane resins, polycarbonate, polyvinylbutyral, cellulose esters, polyacrylamide, saturated polyesters, phenolresins, phenoxy resins, polyamide-imide resins, polyamic acid resins,and epoxy resins. Preferred of them are polystyrene, (meth)acrylicacid-methyl acrylate copolymers, and epoxy resins.

The amount of the other organic polymer, when used in combination, ispreferably 10 to 500 parts by mass per 100 parts by mass of theethylenically unsaturated polymerizable compound.

The photosensitive composition may furthermore contain a monomer havingan unsaturated bond, a chain transfer agent, a surfactant, and so on.

Examples of the monomer having an unsaturated bond include2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, isobutyl acrylate,n-octyl acrylate, isooctyl acrylate, isononyl acrylate, stearylacrylate, methoxyethyl acrylate, dimethylaminoethyl acrylate, zincacrylate, 1,6-hexanediol diacrylate, trimethylolpropane triacrylate,2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, butylmethacrylate, t-butyl methacrylate, cyclohexyl methacrylate,trimethylolpropane trimethacrylate, dipentaerythritol pentaacrylate,dipentaerythritol hexaacrylate, pentaerythritol tetraacrylate,pentaerythritol triacrylate, bisphenol A diglycidyl ether(meth)acrylate, bisphenol F diglycidyl ether (meth)acrylate, bisphenol Zdiglycidyl ether (meth)acrylate, and tripropylene glycoldi(meth)acrylate.

Examples of the chain transfer agent include mercapto compounds, such asthioglycolic acid, thiomalic acid, thiosalicylic acid,2-mercaptopropionic acid, 3-mercaptopropionic acid, 3-mercaptobutyricacid, N-(2-mercaptopropionyl)glycine, 2-mercaptonicotinic acid,3-[N-(2-mercaptoethyl)carbamoyl]propionic acid,3-[N-(2-mercaptoethyl)amino]propionic acid,N-(3-mercaptopropionyl)alanine, 2-mercaptoethane sulfonic acid,3-mercaptopropanesulfonic acid, 4-mercaptobutanesulfonic acid, dodecyl(4-methylthio)phenyl ether, 2-mercaptoethanol,3-mercapto-1,2-propanediol, 1-mercapto-2-propanol, 3-mercapto-2-butanol,mercaptophenol, 2-mercaptoethylamine, 2-mercaptoimidazole,2-mercapto-3-pyridinol, 2-mercaptobenzothiazole, mercaptoacetic acid,trimethylolpropane tris(3-mercaptopropionate), and pentaerythritoltetrakis(3-mercaptopropionate); disulfide compounds obtained byoxidizing the recited mercapto compounds; and iodized alkyl compounds,such as iodoacetic acid, iodopropionic acid, 2-iodoethanol,2-iodoethanesulfonic acid, and 3-iodopropanesulfonic acid.

Examples of the surfactant include fluorine-containing surfactants, suchas perfluoroalkylphosphoric esters, perfluoroalkylcarboxylic acid salts;anionic surfactants, such as higher fatty acid alkali salts,alkylsulfonic acid salts, and alkylsulfuric acid salts; cationicsurfactants, such as higher amine halogenic acid salts and quaternaryammonium salts; nonionic surfactants, such as polyethylene glycol alkylethers, polyethylene glycol fatty acid esters, sorbitan fatty acidesters, and fatty acid monoglycerides; amphoteric surfactants, andsilicone surfactants. These surfactants may be used in combinationthereof.

If desired, the photosensitive composition may contain otherphotopolymerization initiator or sensitizer in addition to the oximeester compound of the invention. A combined use of the otherphotopolymerization initiator can produce marked synergistic effects.

Known photopolymerization initiators may be used in combination with theoxime ester compound of the invention. Examples of such initiatorsinclude benzophenone, phenyl biphenyl ketone,1-hydroxy-1-benzoylcyclohexane, benzoin, benzyl dimethyl ketal,1-benzyl-1-dimethylamino-1-(4′-morpholinobenzoyl)propane,2-morpholyl-2-(4′-methylmercapto)benzoylpropane, thioxanthone,1-chloro-4-propoxythioxanthone, isopropylthioxanthone,diethylthioxanthone, ethylanthraquinone, 4-benzoyl-4′-methyldiphenylsulfide, benzoin butyl ether, 2-hydroxy-2-benzoyl-propane,2-hydroxy-2-(4′-isopropyl)benzoylpropane,4-butylbenzoyltrichloromethane, 4-phenoxybenzoyldichloromethane, methylbenzoylformate, 1,7-bis(9′-acridinyl) heptane,9-n-butyl-3,6-bis(2′-morpholinoisobutyroyl)carbazole, 2-methyl-4,6-bis(trichloromethyl)-s-triazine,2-phenyl-4,6-bis(trichloromethyl)-s-triazine,2-naphthyl-4,6-bis(trichloromethyl)-s-triazine,2,2-bis(2-chlorophenyl)-4,5,4′,5′-tetraphenyl-1,2′-biimidazole,4,4-azobisisobutyronitrile, triphenylphosphine, camphorquinone; N-1414,N-1717, N-1919, and PZ-408 (from ADEKA Corp.); Irgacure 369, Irgacure907, Irgacure OXE 01, and Irgacure OXE 02 (from Ciba SpecialtiesChemicals Corp.); benzoyl peroxide, and compounds represented by generalformulae (III) to (V) shown below. These photopolymerization initiatorscan be used either individually or in a combination of two or morethereof. The amount of the known photopolymerization initiator(s), ifused, is preferably equal to or less than the amount of the oxime estercompound of the invention.

wherein R¹ and R² are as defined for general formula (I); R⁶ has thesame meaning as R¹; Y² represents a halogen atom or an alkyl group; andn represents 0 to 5.

wherein R¹ and R² are as defined for general formula (I); R⁶, Y² and nare as defined for general formula (III); R′¹, R′², and R′⁶ have thesame meaning as R¹; Y′² has the same meaning as Y²; R⁷ represents a diolresidue or a dithiol residue; and Z² represents an oxygen atom or asulfur atom.

wherein R¹ and R² are as defined for general formula (I); R⁶, Y², and nare as defined for general formula (III); Z³ represents an oxygen atom,a sulfur atom, or a selenium atom; A represents a heterocyclic group; prepresents an integer of 0 to 5; and q is 0 or 1.

If desired, the photosensitive composition of the present invention maycontain commonly used additives, including thermal polymerizationinhibitors (e.g., p-anisole, hydroquinone, pyrocatechol,t-butylcatechol, and phenothiazine), plasticizers, adhesionaccelerators, fillers, anti-foaming agents, leveling agents, surfacemodifiers, antioxidants, ultraviolet absorbers, dispersing aids,anti-coagulants, catalysts, effect accelerators, sensitizers,crosslinking agents, and thickeners.

The amounts of the optional components other than the ethylenicallyunsaturated polymerizable compound and the oxime ester compound, exceptthe above described other photopolymerization initiator, inorganicfiller, colorant, and solvent, in the photosensitive composition aredecided as appropriate to the use of the composition. Preferably, thetotal amount of the optional components is not more than 50 parts bymass per 100 parts by mass of the ethylenically unsaturatedpolymerizable compound.

The photosensitive composition of the invention is applied to asubstrate, such as soda glass, quartz glass, semiconductor substrates,metals, paper, or plastics. The method of application is not limited.Any known coating methods may be used, such as spin coating, rollcoating, bar coating, die coating, curtain coating, printing, anddipping. The photosensitive composition may be once applied to a carriersubstrate, such as a film, and then transferred to another substrate.

The photosensitive composition of the invention has unlimitedapplication. It finds use in, for example, photocuring paints orvarnishes, photocuring adhesives, printed boards; color filters forliquid crystal color display devices, such as TV monitors, PC monitors,personal digital assistances, and digital cameras; electrode materialsfor plasma display panels; powder coatings, printing inks, printingplates, adhesives, compositions for dental use, gel coats, photoresistsfor electronics, electroplating resists, etching resists, liquid and dryfilms, soldering resists; resists for manufacturing color filters ofvarious displays or for forming structures in the manufacture of plasmadisplay panels, electroluminescent displays, and LCDs; encapsulatingcompositions for electric/electronic components, magnetic recordingmaterials, fine machine parts, waveguides, optical switches, platingmasks, etching masks, color test systems, glass fiber cable coatings,screen printing stencils, materials for making a three-dimensionalobject by stereolithography, holographic recording materials, imagerecording materials, fine electronic circuits, decolorizing materials,decolorizing materials for image recording materials, decolorizingmaterials for image recording materials using microcapsules, photoresistmaterials for printed wiring boards, photoresist materials for directimage writing using UV and visible lasers, and photoresist materials orprotective layers used to form dielectric layers in the fabrication ofmultilayered printed circuit boards.

The photosensitive composition containing the oxime ester compound ofthe invention can be cured with active light from light sources emittinglight of wavelengths of from 300 to 450 nm. Such light sources includean ultrahigh pressure mercury lamps, mercury vapor arcs, carbon arcs,and xenon arcs.

EXAMPLES

The present invention will now be illustrated in greater detail withreference to Examples, but it should be understood that the invention isnot deemed to be limited thereto.

Example 1-1 Preparation of Compound No. 1 Step 1—Preparation of SulfideCompound

In a nitrogen atmosphere, 15.8 g (100 mmol) of p-chloronitrobenzene,12.1 g (110 mmol) of thiophenol, and 69.4 g of dimethylacetamide wereput in a reactor, and 12.5 g (150 mmol) of sodium hydroxide was addedthereto, followed by stirring at 50° C. for 1 hour. After cooling toroom temperature, the reaction mixture was subjected to oil-waterseparation using ethyl acetate/water. The solvent was removed byevaporation to give 23.1 g of a sulfide compound as yellow crystals(yield: 99%; HPLC purity: 99%).

Step 2—Preparation of Acylated Compound

In a nitrogen atmosphere 12.0 g (90 mmol) of aluminum chloride and 27.0g of dichloroethane were put in a reactor. To the reactor were slowlyadded dropwise 3.56 g (45 mmol) of acetyl chloride, 5.78 g (25 mmol) ofthe sulfide compound obtained in step 1 above, and 27.0 g ofdichloroethane in the order described under cooling with ice, followedby stirring at 5° C. for 30 minutes. The reaction mixture was pouredinto ice-water for oil-water separation. The solvent was removed, andthe residue was recrystallized from ethyl acetate to give 2.94 of anacylated compound as pale yellow crystals (yield: 43%; HPLC purity:96%).

Step 3—Preparation of Compound No. 1

In a nitrogen atmosphere 2.73 g (10 mmol) of the acylated compoundobtained in step 2 above, 1.04 g (15 mmol) of hydroxylaminehydrochloride, and 5.8 g of dimethylacetamide were put in a reactor andstirred at 80° C. for 1 hour. After cooling to room temperature, thereaction system was subjected to oil-water separation. The solvent wasremoved by evaporation, and 10.0 g of butyl acetate and then 1.23 g (12mmol) of acetic anhydride were added to the residue, followed bystirring at 90° C. for 1 hour, followed by cooling to room temperature.The reaction mixture was neutralized with a 5% aqueous solution ofsodium hydroxide. After oil-water separation, the solvent was removed,and the residue was recrystallized from ethyl acetate to afford 2.41 gof pale yellow crystals (yield: 73%; HPLC purity: 99%), which wereidentified to be compound No. 1 as a result of various analyses. Theresults of analyses are shown below.

(1) Melting point: 91.9° C.

(2) ¹H-NMR spectrum (ppm)

2.29 (s:3H), 2.42 (s:3H), 7.28 (d:2H), 7.53 (d:2H), 7.81 (d:2H), 8.10(d:2H)

(3) IR spectrum (cm⁻¹)

1775, 1592, 1576, 1519, 1477, 1393, 1368, 1342, 1316, 1203, 1115, 1085,1009, 993, 939, 902, 853, 846, 836, 741, 682, 639

(4) UV spectrum (in chloroform)

λ_(max)=346 nm

(5) Decomposition temperature (5% mass loss temperature at heating rateof 10° C./min in nitrogen atmosphere)

270° C.

Example 1-2 Preparation of Compound No. 23

Compound No. 23 was prepared in the same manner as in Example 1-1,except for replacing acetyl chloride used in step 2 with dodecanoylchloride. The acylated compound as an intermediate was obtained in ayield of 30% with an HPLC purity of 99%. The yield and the HPLC purityof compound No. 23 were 66% and 99%, respectively. The results ofanalyses of compound No. 23 are shown below.

(1) Melting point: 73.9° C.

(2) ¹H-NMR spectrum (ppm)

0.88 (t:3H), 1.20˜1.49 (m:16H), 1.58 (tt:2H), 2.28 (s:3H), 2.86 (t:2H),7.25 (d:2H), 7.54 (d:2H), 7.77 (d:2H), 8.10 (d:2H)

(3) IR spectrum (cm⁻¹)

3095, 2917, 2851, 1766, 1598, 1517, 1471, 1397, 1365, 1348, 1284, 1204,1083, 1000, 946, 895, 853, 837, 745, 720, 686

(4) UV spectrum (in chloroform)

λ_(max)=341 nm

(5) Decomposition temperature (5% mass loss temperature at heating rateof 10° C./min in nitrogen atmosphere)

255° C.

Example 1-3 Preparation of Compound No. 24

Compound No. 24 was prepared in the same manner as in Example 1-1,except for replacing acetyl chloride used in step 2 with dodecanoylchloride and replacing acetic anhydride used in step 3 with benzoylchloride and triethylamine. The acylated compound as an intermediate wasobtained in a yield of 30% with an HPLC purity of 99%. The yield and theHPLC purity of compound No. 24 were 64% and 99%, respectively. Theresults of analyses of compound No. 24 are shown below.

(1) Melting point: 92.0° C.

(2) ¹H-NMR spectrum (ppm)

0.87 (t:3H), 1.20-1.49 (m:16H), 1.69 (tt:2H), 2.99 (t:2H), 7.27(ddd:2H), 7.52 (dd:2H), 7.57 (ddd:2H), 7.64 (tt:1H), 7.86 (ddd:2H), 8.11(ddd:2H), 8.13 (d:2H)

(3) IR spectrum (cm⁻¹)

2952, 2918, 2849, 1749, 1593, 1575, 1509, 1470, 1449, 1340, 1243, 1177,1110, 1082, 1065, 1022, 919, 884, 846, 784, 744, 722, 707, 680

(4) UV spectrum (in chloroform)

λ_(max)=341 nm

(5) Decomposition temperature (5% mass loss temperature at heating rateof 10° C./min in nitrogen atmosphere)

245° C.

Example 2 Preparation of Photosensitive Composition No. 1

To 14.0 g of an acrylic copolymer were added 5.90 g oftrimethylolpropane triacrylate, 2.70 g of compound No. 1 obtained inExample 1-1, and 79.0 g of ethyl cellosolve, and the mixture wasthoroughly stirred to obtain photosensitive composition No. 1.

The acrylic copolymer used above was obtained by dissolving 20 parts bymass of methacrylic acid, 15 parts by mass of hydroxyethyl methacrylate,10 parts by mass of methyl methacrylate, and 55 parts by mass of butylmethacrylate in 300 parts by mass of ethyl cellosolve, adding thereto0.75 parts by mass of azobisisobutyronitrile, followed by heating at 70°C. for 5 hours in a nitrogen atmosphere.

Examples 3-1 to 3-3 Preparation of Photosensitive Composition Nos. 2-1to 2-3

Dipentaerythritol pentaacrylate (15.0 g) and 3.74 g of 1,4-butanedioldiglycidyl ether were mixed, and 3.30 g of compound No. 1 obtained inExample 1-1, compound No. 23 obtained in Example 1-2, or compound No. 24obtained in Example 1-3, and 78 g of ethyl cellosolve were addedthereto, followed by thoroughly stirring to make photosensitivecomposition No. 2-1, 2-2, or 2-3, respectively.

Examples 4-1 to 4-3 Preparation of Photosensitive Composition Nos. 3-1to 3-3 as Alkali-Developable Photosensitive Resin Compositions Step1—Preparation of Alkali Developable Resin Composition No. 1

A reactor was charged with 17.0 g of1,1-bis(4′-epoxypropyloxyphenyl)-1-(1″-biphenyl)-1-cyclohexylmethane,4.43 g of acrylic acid, 0.06 g of 2,6-di-tert-butyl-p-cresol, 0.11 g oftetrabutylammonium acetate, and 14.3 g of propylene glycol 1-monomethylether 2-acetate, and the mixture was stirred at 120° C. for 16 hours.The reaction system was cooled to room temperature, and 7.18 g ofpropylene glycol 1-monomethyl ether 2-acetate, 4.82 g of succinicanhydride, and 0.25 g of tetrabutylammonium acetate were added thereto,followed by stirring at 100° C. for 5 hours. To the mixture were furtheradded 5.08 g of1,1-bis(4′-epoxypropyloxyphenyl)-1-(1″-biphenyl)-1-cyclohexylmethane and2.18 g of propylene glycol 1-monomethyl ether 2-acetate, and the mixturewas stirred at 120° C. for 12 hours, 80° C. for 2 hours, and 40° C. for2 hours. Finally, 13.1 g of propylene glycol 1-monomethyl ether2-acetate was added to provide alkali developable resin composition No.1 in the form of a propylene glycol 1-monomethyl ether 2-acetatesolution (Mw=4200; Mn=2100; acid value (solid basis): 55 mg-KOH/g).

Step 2—Preparation of Photosensitive Composition Nos. 3-1 to 3-3

Alkali developable resin composition No. 1 obtained in step 1 (2.68 g),0.73 g of trimethylolpropane triacrylate, 7.91 g of propylene glycol1-monomethyl ether 2-acetate, and 5.18 g of cyclohexanone were mixed. Tothe mixture was added 1.58 g of compound No. 1 obtained in Example 1-1,compound No. 23 obtained in Example 1-2, or compound No. 24 obtained inexample 1-3, followed by stirring well to give photosensitivecomposition No. 3-1, 3-2, or 3-3, respectively, as an alkali developablephotosensitive resin composition.

Example 5 Preparation of Photosensitive Composition No. 4 asAlkali-Developable Photosensitive Resin Composition Step 1—Preparationof Alkali Developable Resin Composition No. 2

A reactor was charged with 184 g of a bisphenol fluorene epoxy resin(epoxy equivalent: 231), 58.0 g of acrylic acid, 0.26 g of2,6-di-tert-butyl-p-cresol, 0.11 g of tetrabutylammonium acetate, and23.0 g of propylene glycol 1-monomethyl ether 2-acetate, and the mixturewas stirred at 120° C. for 16 hours. After cooling to room temperature,35.0 g of propylene glycol 1-monomethyl ether 2-acetate, 59.0 g ofbiphthalic anhydride, and 0.24 g of tetra-n-butylammonium bromide wereadded to the reaction system, followed by stirring at 120° C. for 4hours. To the mixture were further added 20 g of tetrahydrophthalicanhydride, and the mixture was stirred at 120° C. for 4 hours, 100° C.for 3 hours, 80° C. for 4 hours, 60° C. for 6 hours, and 40° C. for 11hours. Finally, 90.0 g of propylene glycol 1-monomethyl ether 2-acetatewas added to provide alkali developable resin composition No. 2 in theform of a propylene glycol 1-monomethyl ether 2-acetate solution(Mw=5000; Mn=2100; acid value (solid basis): 92.7 mg-KOH/g).

Step 2—Preparation of Photosensitive Composition No. 4

Alkali developable resin composition No. 2 obtained in step 1 (2.68 g),0.73 g of trimethylolpropane triacrylate, 7.91 g of propylene glycol1-monomethyl ether 2-acetate, and 5.18 g of cyclohexanone were mixed.Compound No. 1 obtained in Example 1-1 (1.58 g) was added thereto togive photosensitive resin composition No. 4 as an alkali developablephotosensitive resin composition.

Example 6 Preparation of Photosensitive Composition No. 5 as ColoredAlkali-Developable Photosensitive Resin Composition

Photosensitive composition Nos. 5-1 to 5-3 as colored alkali-developablephotosensitive resin compositions were prepared in the same manner as inExamples 4-1 to 4-3, except for further adding 2.00 g of pigment blue15.

Example 7 Preparation of Photosensitive Composition No. 6 as ColoredAlkali-Developable Photosensitive Resin Composition

Photosensitive composition No. 6 as a colored alkali-developablephotosensitive resin composition was prepared in the same manner as inExample 5, except for further adding 3.00 g of carbon black.

Comparative Example 1 Preparation of Photosensitive Composition No. 7

Photosensitive resin composition No. 7 for comparison was prepared inthe same manner as in Example 3-1, except for replacing 3.30 g ofcompound No. 1 obtained in Example 1-1 with 3.30 g of comparativecompound 1 shown below.

Comparative Example 2 Preparation of Photosensitive Composition No. 8

Photosensitive resin composition No. 8 for comparison was prepared inthe same manner as in Example 3-1, except for replacing 3.30 g ofcompound No. 1 obtained in Example 1-1 with 1.58 g of comparativecompound 2 below.

Comparative Example 3 Preparation of Photosensitive Composition No. 9 asAlkali Developable Photosensitive Resin Composition

Photosensitive resin composition No. 9 as an alkali developablephotosensitive resin composition for comparison was prepared in the samemanner as in Example 4-1, except for replacing 1.58 g of compound No. 1obtained in example 1-1 with the same amount of comparative compound 1.

Comparative Example 4 Preparation of Photosensitive Composition No. 10as Alkali Developable Photosensitive Resin Composition

Photosensitive resin composition No. 10 as an alkali developablephotosensitive resin for comparison was prepared in the same manner asin Example 4-1, except for replacing 1.58 g of compound No. 1 obtainedin example 1-1 with the same amount of comparative compound 2.

Example 8 Preparation of Photosensitive Composition No. 11

Photosensitive composition No. 11 was prepared in the same manner as inExample 2, except for further adding 4.52 g of titanium oxide.

Photosensitive composition Nos. 2-1 to 2-3 and photosensitivecomposition Nos. 7 and 8 for comparison were tested for hardness asfollows. The test results obtained are shown in Table 1.

Photosensitive composition Nos. 3-1 to 3-3 and comparativephotosensitive composition Nos. 9 and 10, each of which was an alkalidevelopable photosensitive resin composition, were evaluated forsensitivity as follows. The results are shown in Table 2.

(1) Hardness Test

The photosensitive composition was applied to a 50 μm thick polyethyleneterephthalate film with a #3 bar coater and irradiated with light of ahigh pressure mercury lamp (80 W/cm) using a light irradiator equippedwith a belt conveyor. The distance between the lamp and the beltconveyor was 10 cm. The linear speed of the belt conveyor was 8 cm/min.After the thus cured coating layer was left to stand at room temperaturefor 24 hours, the hardness was determined using a pencil hardness testerunder a load of 1 kg.

(2) Sensitivity

The alkali developable photosensitive resin composition was applied toan aluminum plate with a #3 bar coater to a thickness of about 1 μm,prebaked at 60° C. for 15 minutes, and exposed to light using spectralirradiation equipment CT-25CP form JASCO Corp. equipped with anultra-high pressure mercury lamp. The exposed coating layer was immersedin a 2.5 mass % solution of sodium carbonate at 25° C., followed bythoroughly washing with water. The spectral sensitivity was evaluated interms of the minimum energy of light at 365 nm and 405 nm required forcuring, which was obtained from the coating layer remaining on thealuminum plate and the amount of applied light at 365 nm and 405 nm.

TABLE 1 Pencil Photosensitive Composition Test Compound Hardness No. 2-1(Example 3-1) Compound No. 1 3H No. 2-2 (Example 3-2) Compound No. 23 3HNo. 2-3 (Example 3-3) Compound No. 24 3H No. 7 (Comparative Example 1)Comparative Compound 1 1H No. 8 (Comparative Example 2) ComparativeCompound 2 2H

TABLE 2 Sensitivity (mJ/cm²) Photosensitive Composition Test Compound365 nm 405 nm No. 3-1 (Example 4-1) Compound No. 1 3.4 24.7 No. 3-2(Example 4-2) Compound No. 23 3.3 42.8 No. 3-3 (Example 4-3) CompoundNo. 24 3.3 4.3 No. 9 (Comparative Comparative 608 0 Example 3) Compound1 No. 10 (Comparative Comparative 6.1 782 Example 4) Compound 2

As is apparent from Table 1, photosensitive composition Nos. 2-1 to 2-3of Examples 3-1 to 3-3 gained high hardness on curing, whereasphotosensitive composition No. 7 of Comparative Example 1 andphotosensitive composition No. 8 of Comparative Example 2 failed toprovide sufficient hardness.

As is apparent from table 2, alkali developable photosensitive resincomposition Nos. 3-1 to 3-3 of Examples 4-1 to 4-3 exhibited highsensitivity to light of long wavelengths, i.e., 365 nm and 405 nm,whereas photosensitive resin composition No. 9 of Comparative Example 3required an increased amount of energy for exposure at 365 nm on accountof low sensitivity to that wavelength of light and did not cure withlight at 405 nm. Photosensitive composition No. 10 of ComparativeExample 4 had sufficient sensitivity to light at 365 nm but required anincreased amount of energy for exposure at 405 nm on account of lowsensitivity.

INDUSTRIAL APPLICABILITY

The oxime ester compound of the invention exhibits highphotosensitivity, particularly to radiation of emission lines at longwavelengths, 365 nm (i-ray) and 405 nm (h-ray), and is therefore usefulas a photopolymerization initiator.

1. An oxime ester compound represented by general formula (I):

wherein R¹ and R² each independently represent R¹¹, COR¹¹, OR¹¹, SR¹¹,CONR¹²R¹³, or CN; R¹¹, R¹², and R¹³ each represent a hydrogen atom, analkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 30carbon atoms, an arylalkyl group having 7 to 30 carbon atoms, or aheterocyclic group having 2 to 20 carbon atoms, the alkyl group, thearyl group, the arylalkyl group, and the heterocyclic group optionallysubstituted with OR²¹, COR²¹, SR²¹, NR²²R²³, CONR²²R²³, —NR²²—OR²³,—NCOR²²—OCOR²³, —C(═N—OR²¹)—R²², —C(═N—OCOR²¹)—R²², CN, a halogen atom,—CR²¹═CR²²R²³, —CO—CR²¹═CR²²R²³, a carboxyl group, or an epoxy group;R²¹, R²², and R²³ each independently represent a hydrogen atom, an alkylgroup having 1 to 20 carbon atoms, an aryl group having 6 to 30 carbonatoms, an arylalkyl group having 7 to 30 carbon atoms, or a heterocyclicgroup having 2 to 20 carbon atoms; the methylene units of the alkylenemoiety of the substituents represented by R¹¹, R¹², R¹³, R²¹, R²², andR²³ may be interrupted by an unsaturated linkage, an ether linkage, athioether linkage, an ester linkage, a thioester linkage, an amidolinkage, or a urethane linkage at 1 to 5 sites thereof; the alkyl moietyof the substituents represented by R¹¹, R¹², R¹³, R²¹, R²², and R²³ maybe branched or cyclic; an alkyl terminal of the substituents representedby R¹¹, R¹², R¹³, R²¹, R²², and R²³ may have an unsaturated bond; R¹²and R¹³, and R²² and R²³ may be connected to each other to form a ring;R³ and R⁴ each independently represent R¹¹, OR¹¹, SR¹¹, COR¹¹,CONR¹²R¹³, NR¹²COR¹¹, OCOR¹¹, COOR¹¹, SCOR¹¹, OCSR¹¹, COSR¹¹, CSOR¹¹,CN, a halogen atom, or a hydroxyl group; a and b each independentlyrepresent an integer of 0 to 4; X represents an oxygen atom, a sulfuratom, a selenium atom, CR³¹R³², CO, NR³³, or PR³⁴; R³¹, R³², R³³, andR³⁴ each independently represent R¹¹, OR¹¹, COR¹¹, SR¹¹, CONR¹²R¹³, orCN; when X is CR³¹R³², R³ and R⁴ may be connected to each other to forma ring, or R³ may be connected to one of the carbon atoms of the benzenering neighboring via —X— to form a cyclic structure; when X is an oxygenatom, a sulfur atom, a selenium atom, or PR³⁴, R³ may be connected toone of the carbon atoms of the benzene ring neighboring via —X— to forma ring, or R³ and R⁴ may be connected to each other to form a ring; andeach of R³¹, R³², R³³, and R³⁴ may independently be connected to eitherone of the neighboring benzene rings to form a ring.
 2. The oxime estercompound according to claim 1, wherein X is a sulfur atom.
 3. The oximeester compound according to claim 1, wherein each of R¹ and R² is anoptionally halogen-substituted, straight-chain, branched, or cyclicalkyl group having 1 to 20 carbon atoms, an optionallyhalogen-substituted aryl group having 6 to 30 carbon atoms, or anoptionally halogen-substituted arylalkyl group with 7 to 30 carbonatoms.
 4. A photopolymerization initiator comprising the oxime estercompound according to claim 1 as an active ingredient.
 5. Aphotosensitive composition comprising the photopolymerization initiatoraccording to claim 4 and a polymerizable compound having anethylenically unsaturated bond.
 6. The photosensitive compositionaccording to claim 5, further comprising an inorganic compound.
 7. Analkali-developable photosensitive resin composition comprising thephotopolymerization initiator according to claim 4 and analkali-developable compound having an ethylenically unsaturated bond. 8.A colored alkali-developable photosensitive resin composition comprisingthe alkali-developable photosensitive resin composition according toclaim 7 and a colorant.
 9. The oxime ester compound according to claim2, wherein each of R¹ and R² is an optionally halogen-substituted,straight-chain, branched, or cyclic alkyl group having 1 to 20 carbonatoms, an optionally halogen-substituted aryl group having 6 to 30carbon atoms, or an optionally halogen-substituted arylalkyl group with7 to 30 carbon atoms.
 10. A photopolymerization initiator comprising theoxime ester compound according to claim 2 as an active ingredient.
 11. Aphotopolymerization initiator comprising the oxime ester compoundaccording to claim 3 as an active ingredient.
 12. A photopolymerizationinitiator comprising the oxime ester compound according to claim 9 as anactive ingredient.